C.-P. Schnorr and M. Jakobsson. Security of discrete log cryptosystems in the random oracle and generic model. In The Mathematics of Public-Key Cryptography. The Fields Institute, 1999.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....scheme [25] with ElGamal encryption scheme under some cryptographic assumption in the random oracle model. Jakobsson used the non malleable ElGamal encryption scheme in his MIX net for users encryption to prevent the repeated ciphertext attack [13] For a detailed study of the security consult [26]. We also use this scheme in our MIX net of Sec. 4. 3 An attack for Jakobsson s practical MIX In this section, we show that the Jakobsson s MIX net of Eurocrypt 98 [13] is broken, which was believed to be t resilient and very efficient. Jakobsson first showed that a MIX net is obtained by ....

C. P. Schnorr and M. Jakobsson, "Security of Discrete Log Cryptosystems in the Random Oracle + Generic Model," http://www.bell-labs.com/user/markusj/

....security results are not applicable to the widely standardized DSA and ECDSA signature schemes, unless the schemes are modi ed so that the signer hashes both the message and the random group element generated, rather than just the message. The provable security results of Jakobsson and Schnorr [10] for certain discrete logarithm based signature schemes work in the combined generic group model of Shoup [13] and the random oracle model. In this paper, we prove that ECDSA is secure against existential forgery by adaptive chosen message attack if the elliptic curve group is modeled by a ....

....forgery by adaptive chosen message attack if the elliptic curve group is modeled by a generic group and if the hash function employed is collision resistant. We also provide an exact security analysis of our proof. Since our proof works in a model which is weaker than the combined model of [10], our proofs give a stronger security assurance. Curiously, our proof technique does not appear to be applicable to proving the security of DSA. 1 Introduction The Elliptic Curve Digital Signature Algorithm (ECDSA) is a widely standardized signature scheme [1, 7, 9] It is therefore important ....

[Article contains additional citation context not shown here]

M. Jakobsson and C. P. Schnorr, Security of discrete log cryptosystems in the random oracle + generic model, Conference on the Mathematics of PublicKey Cryptography, The Fields Institute, Toronto, Canada, 1999, Available at http://www.mi.informatik.uni-frankfurt.de/research/papers.html.

.... the value of the Di#e Hellman secret key g xy from the known values of g x and g y is a hard computational problem, see [12, 22] However, very few rigorously proved results of this kind are known for this and for the closely related problem of computing the discrete logarithm, see [1, 2, 5, 6, 7, 8, 11, 14, 16, 17, 18, 19, 21]. In particular, polynomial representations of the Di#e Hellman key in the diagonal case x = y have recently been considered in [2] Among other 1 results, it has been shown in [2] that the equation g x 2 = f(g x ) with a polynomial f(U) # IF q [U ] of degree deg f # n is satisfied by ....

C. P. Schnorr and M. Jacobsson, `Security of discrete log cryptosystems in the random oracle + generic model', Preprint , 1999, 1--15.

....elements are equal, as well as to perform group operations. Clearly their bound does not cover the operations of the Shanks and Pollard algorithms, which run in time p 1=2 , not p. Weaker but more realistic lower bounds have also been obtained by Nechaev [Nechaev] and Shoup [Shoup] See also [SchnorrJ]. They show that in certain models of computation, basically, in Shoup s case, ones in which group elements do have unique encodings, but arbitrary ones, with no structure, and in which the algorithm does not have access to the encodings of elements, and has to consult an oracle to perform group ....

C. P. Schnorr and M. Jakobsson, Security of discrete log cryptosystems in the random oracle + generic model, to be published.

....257] Security of DL encryption and signatures against generic attacks a survey Claus Peter Schnorr Abstract. We survey recent results on the security of DL cryptosystems and DL signatures against generic attacks [Sh97, SJ99, SJ00] assuming the random oracle model (ROM) and the generic group model (GM) We comment on the relevance of these results towards applications. Key words and phrases: Generic algorithm, generic group model, random oracle model, signed ElGamal encryption, generalized signed ElGamal encryption, ....

....has no weaknesses. The strong assumption of the ROM GM makes sense in cases where traditional security proofs fail. Prominent examples are the security of Schnorr identi cation against active adversaries shown in [Sh97] security of signed ElGamal encryption [SJ00] and of blind Schnorr signatures [SJ99]. A security proof in the ROM GM encourages further analysis under relaxed assumptions. For instance it is reasonable to ask whether the random function H can be replaced by Canetti s oracle hashing replacing H(z) by (h(z; r) r) for a one way h and a random one time key r. It would be nice to ....

[Article contains additional citation context not shown here]

Schnorr, C.P., Jakobsson, M., Security of discrete log cryptosystems in the random oracle + generic model. TR report University Frankfurt and Bell Laboratories 1999. http:www.mi.informatik.uni-frankfurt.de.

No context found.

C.-P. Schnorr and M. Jakobsson. Security of discrete log cryptosystems in the random oracle and generic model. In The Mathematics of Public-Key Cryptography. The Fields Institute, 1999.

No context found.

C.-P. Schnorr and M. Jakobsson. Security of discrete log cryptosystems in the random oracle and generic model. In The Mathematics of Public-Key Cryptography. The Fields Institute, 1999.

No context found.

Schnorr, C. P., and Jakobsson, M. Security of discrete log cryptosystems in the random oracle + generic model. In Conference on The Mathematics of Public-Key Cryptography (The Fields Institute, Toronto, Canada, 1999).

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC